The present invention pertains to holders for rotary tools and more particularly pertains to a tool cutting system particularly suitable for use with patella cutting blades or other similar tools.
Patella cutters are surgical tools which are used to mill the patella to accommodate the insertion of artificial knee joints. Patella cutting lids are mounted on tool drivers which in turn are mounted in the chuck or collet of a portable drill or flexible powered shaft. Patella cutting lids are separable from their tool drivers in order to be replaced or sharpened as they are used. It also may be necessary to change cutting lids during an operation. Tool drivers are relatively expensive, and thus must be cleaned and reused.
Some previous tool drivers grip the cutting lid by means of a flange and slot and an opposed spring loaded ball catch, like that on a socket wrench or socket driver, or other catch devices. This represents a problem in that the catch tends to trap dried blood and other debris, which is very difficult to remove during cleaning. An additional problem is that unless tolerances of cutting lids and tool drivers are made very close, there is considerable free play between the cutting lid and the tool driver. This increases wear and decreases the precision of the tool.
Additionally, the cutting lids being reused must be removed, cleaned, and sharpened as the cost in manufacturing and producing these highly sophisticated and reusable cutting lids is relatively great. There is also the accompanying cost of making the cutting lids aseptic for each operation.
Patella cutting systems cannot be compared with other surgical tools inasmuch as they are utilized to cut the patella, which together with the skull bone, is the hardest bone in the human body. Furthermore, in knee surgery, the patella must be cut leaving a flat, smooth surface within a relatively high tolerance. Additionally, the bone shavings cut from the patella need to be collected in some surgical techniques to be used in filling bone cavities formed by the surgery and enhancing healing. Because the patella is such a hard bone and patella cutters dull quickly during use, it is highly desirable to provide a patella cutting system in which the cutters are disposable, or if reusable, are easily resharpened, resterilized and reused relatively inexpensively.
The current cutting lids generally are not disposable. They must be cleaned and are costly to manufacture and produce. Additionally, because of their reusable character, there is always the chance that aseptic conditions of the operation are being compromised.
It is therefore highly desirable to provide an improved patella cutting system.
It is also highly desirable to provide an improved pin type tool driver which provides a locking means which can securely hold cutting lids.
It is also highly desirable to provide an improved cutting lid that is disposable.
It is also highly desirable to provide an improved patella cutting system that does not compromise the aseptic conditions of an orthopedic surgery procedure.
It is also highly desirable to provide an improved cutting lid that can be easily joined or disjoined from a tool driver.
It is also highly desirable to provide an improved patella cutting system that is less expensive to manufacture and produce.
It is also highly desirable to provide an improved patella cutting system which eliminates exposed parts which can catch and retain blood and other debris which present cleaning as well as sterilization problems.
It is finally highly desirable to provide an improved pin type tool driver and cutting lid which meet all of the above desired features.